Off lead dog walking in public illegal

Background

I would like Parliament to pass a law please due to a lot of recent attacks on dogs which are on leads which are then attacked , mauled and resulting in some cases the death of family pets, making it illegal for owners to walk dogs off lead.

Additional details

This will result hopefully in less dog attacks and attacks on humans who try to intervene usually resulting in the human getting hurt themselves . A law passed would deter hopefully the mindless owners who have no regard for nervous dogs and owners who feel frightened and let down by authorities , namely the police who very rarely do any thing about these things happening as it is often difficult to trace owners after they leave the scene,